| HS Code | 160824 |
| Material Type | Thermoplastic Elastomer (TPE) |
| Tensile Strength | 5.5 MPa |
| Elongation At Break | 250% |
| Flexural Modulus | 20 MPa |
| Density | 1.10 g/cm³ |
| Bulk Density | 0.50 g/cm³ |
| Particle Size | 20-80 µm |
| Melting Point | 170 °C |
| Heat Deflection Temperature | 60 °C at 0.45 MPa |
| Moisture Absorption | <0.5% |
| Color | White |
As an accredited ALM TPE-210-S Prototyping Polymer factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | Packaged in a sealed 10 kg moisture-barrier foil bag with desiccant, ALM TPE-210-S Prototyping Polymer ensures safe handling and storage. |
| Container Loading (20′ FCL) | ALM TPE-210-S Prototyping Polymer, securely palletized and loaded into a 20′ FCL container for safe ocean freight export. |
| Shipping | Typically shipped as a sealed, moisture-barrier powder in foil bags or drums. It is not classified as dangerous goods for transport under normal conditions. Store dry, closed, away from heat, ignition sources, and incompatible materials. Always consult the current safety data sheet and local regulations. |
| Storage | Store ALM TPE-210-S Prototyping Polymer in its original, tightly sealed container in a cool, dry, well-ventilated area. Protect from moisture, direct sunlight, heat, sparks, flames, and static discharge. Maintain recommended temperature, typically 15–25°C, and avoid dust clouds. Keep away from incompatible oxidizers, foodstuffs, and ignition sources. Always follow the supplier’s SDS and local storage regulations. |
| Shelf Life | Typically 12 months when stored sealed in original packaging under cool, dry conditions, away from moisture, heat, and direct sunlight. |
During low-volume instrument panel, door trim, and center console soft-surface validation with ALM TPE-210-S Prototyping Polymer, an 80–150 t hydraulic injection molding machine with an L/D 20:1 general-purpose screw and valve-gated hot runner is operated at melt 190–210 °C. The grade replicates VDI 24–27 mold textures within this window. Texture replication below 180 °C is insufficient because zero-shear viscosity rises above 450 Pa·s, while flash into venting grooves above 220 °C corresponds to a viscosity drop below 120 Pa·s. Nozzle band temperature is therefore held within ±2 °C. P20 mold steel with draft angle 3°–5° and demolding surface temperature below 45 °C are used to prevent texture peel and sticking in short-run validation tools.
Automotive interior compliance testing for this material is anchored to ISO 3795 horizontal burn rate, DIN 75201:2011 gravimetric fogging with total condensate below 2.0 mg, VDA 278:2011 VOC/FOG emission limits, and REACH Regulation EC 1907/2006 SVHC screening. For overmolded polypropylene substrates, the formulation uses ALM TPE-210-S as the soft phase with 2.0–4.0 wt% maleic anhydride grafted PP tie resin. Standalone soft parts use no tie resin. White mineral oil is limited to 5 phr maximum because higher oil loading raises fogging condensate and surface tack after heat aging. A hindered amine light stabilizer package at 0.2–0.5 wt% is retained in black and dark-gray formulations to reduce surface microcracking after 500 h xenon arc exposure.
The downstream production sequence for automotive validation parts includes PP substrate injection at 230 °C and 30–45 MPa hold pressure, followed by automated insert transfer into a second cavity for TPE overmolding. The TPE layer is filled through a sequential valve gate at 0.8–1.3 mm nominal thickness, with hold pressure 25–40 MPa for 4–8 s, cooling 12–18 s, and total cycle 35–50 s. In-mold residence time above 8 min at 200 °C causes styrenic domain chain scission and hardness drift of +3–5 Shore A. Regrind is kept at or below 20 wt%, and regrind particles are dried to 0.03 wt% moisture before reintroduction to the feed throat.
Terminal finished prototype families include instrument panel topper pads, door trim mid-panel inserts, center console armrest covers, glove box soft-touch lids, HVAC control knobs, and shift gaiter collars.
Because the rubbery phase coalesces only when mold surface temperature exceeds the upper glass transition temperature of the styrenic end-blocks, Shore hardness replication in medical cushion prototypes using ALM TPE-210-S is governed by melt compressibility and mold temperature stability. At a target Shore A of 40–48, shot-to-shot hardness variation is contained within ±1.5 Shore A when mold temperature is 35–45 °C and clamp force is 60–120 t. A mold surface below 30 °C produces skin-core hardness differences of 3–4 Shore A because the surface freezes before the rubbery network fully coalesces. Gate freeze time is adjusted to 1.5–2.5 s using valve-gate or cold sprue drops, preventing sink and sticking on low-durometer parts.
Regulatory assessment for short-term skin-contact prototypes addresses ISO 10993-5:2009 for cytotoxicity, ISO 10993-10:2010 for skin sensitization, ISO 10993-23:2021 for irritation, and ISO 10993-11:2017 for acute systemic toxicity. Where an FDA pre-submission is required, USP Class VI extraction data and FDA 21 CFR 177.2600 food-contact references are used only as supplementary chemical resistance references; they do not replace device-specific biological evaluation. The compliance matrix below is applied to each short-run prototype family.
| Cytotoxicity | ISO 10993-5:2009, L-929 extract dilution | Cell viability ≥ 70% |
| Skin irritation | ISO 10993-23:2021, reconstructed human epidermis | Viability ≥ 50% |
| Skin sensitization | ISO 10993-10:2010, LLNA or guinea pig maximization | No erythema or oedema beyond grade 1 |
| Acute systemic toxicity | ISO 10993-11:2017, saline and vegetable oil extracts | No signs of systemic toxicity |
Formulation for medical cushion prototypes uses rubber-grade white mineral oil at 20–35 phr, non-cytotoxic masterbatch pigments at 1.0–2.0 wt%, and a processing stabilizer at 0.1–0.3 wt%. Regrind above 5 wt% is excluded because biological requalification of reprocessed material would be required. Silicone oil is not added because it interferes with pressure-sensitive adhesive bonding used in wearable patch prototypes.
Production is carried out in ISO 13485:2016-aligned cleanroom injection cells with 20–30 t electric machines. Cold runner sprue bushings are preferred over hot runner drops because hot runner residence time above 240 °C·min can cause yellowing and high molecular weight tail formation. Melt temperature is 180–200 °C, back pressure 3–6 MPa, screw speed 50–80 rpm, and mold texture SPI/SPE B-1 to A-1. Ethylene oxide sterilization compatibility is evaluated under ISO 11135:2014; published data for this specific grade under gamma sterilization above 25 kGy is limited, so ISO 11137-2:2013 dose mapping is required before terminal sterilization use.
Terminal finished prototype types include ergonomic MRI coil cushion pads, respiratory mask fit-test seals, diagnostic probe handle inserts, wearable patch enclosures, and hospital bed rail corner guards. Operational boundaries include avoiding steam autoclave temperatures of 121 °C unless cycle compatibility is proven, and limiting repeated exposure to quaternary ammonium disinfectants because cationic surfactants can stress-crack styrenic TPE surfaces.
In connector sealing and button membrane prototyping, ALM TPE-210-S is processed on 15–25 t electric micro-injection machines with L/D 22:1 screws to fill wall sections down to 0.4 mm. For USB-C port gaskets and SIM card slot seals, melt temperature is 185–205 °C and mold temperature 25–35 °C; the lower mold temperature keeps flatness below 0.1 mm across a 20 mm sealing envelope but reduces gloss uniformity. Flash generation in sub-0.5 mm parting lines occurs when holding pressure exceeds 60 MPa on unfilled TPE-S, so pressure-limited injection with cavity pressure transducers is used to stop the screw at the first evidence of parting-line lift.
Compliance references include IEC 60529:1989+A2:2013 IP67 immersion testing, UL 94 HB flame classification, RoHS 2011/65/EU Annex II restrictions, and REACH Regulation EC 1907/2006 SVHC screening. The unfilled grade is not UL 94 V-0; any protrusion near lithium battery vents requires additional flame propagation and temperature review because TPE-S can lose tensile strength above 90 °C under continuous load.
Formulation additions for connector sealing include a non-siloxane slip additive at 0.5–1.5 wt% to reduce insertion force by 20–30% relative to unmodified TPE-S. In dark colors, carbon black is used at 0.5–2.0 wt%; above 3.0 wt% surface resistivity drops below 10⁶ Ω/sq and the part becomes static-dissipative rather than insulating. A hindered phenolic antioxidant at 0.1–0.3 wt% resists yellowing after 72 h at 70 °C. White oil is maintained below 15 phr to limit migration into ABS or PC housings.
Part filling for button membranes and gaskets uses cold sprue direct edge gates or tunnel gates; valve-gate hot runners are avoided when shot mass is under 0.8 g because gate vestige control below 0.05 mm is difficult. Ejector pins use 0.5–1.0 mm pads, and air blow-off is not recommended because oil-containing TPE-S retains surface charge. Vision inspection checks gate blush and flash, while CMM verifies sealing bead height tolerance at ±0.05 mm.
Terminal finished prototype parts include IP-rated connector seals, SIM card grommets, button membranes for handheld terminals, speaker mesh overmolded gaskets, camera bezel cushioning rings, and stylus grip sleeves. Published data for ALM TPE-210-S in specific connector geometries with complex undercuts is limited; seal force retention after 5,000 cycles should be fixture-validated under EIA 364-13.
Before 30 Shore A formulations enter the barrel, moisture uptake above 0.03 wt% in ALM TPE-210-S pellets creates silver streaking on midsole sidewalls and reduces tensile strength at break by 8–12% relative to dried material when tested under ISO 37:2017. The failure mechanism is not hydrolytic chain scission because the SEBS midblock is saturated; it is steam nucleation at the melt front when water flashes above 180 °C. Desiccant drying at 70 °C for 2 h with a -40 °C dew point is required when ambient relative humidity exceeds 60%. Wet material also causes siping weld line disruption and density variation in foamed prototypes.
Footwear prototype evaluation uses ISO 17707:2005 flex fatigue for outsoles, DIN 53516:2009 abrasion resistance, ISO 815-1:2019 compression set at 23 °C and 70 °C, and SATRA TM144 sole bond peel. The unfilled 30 Shore A formulation is used for cushioning and energy return validation, not for high-wear outsole surfaces; its DIN abrasion performance is below that of compounded rubber outsoles.
Formulation for midsole prototypes uses 100 phr ALM TPE-210-S, microcellular blowing agent masterbatch at 0.8–1.5 wt% for a density reduction target of 15–25%, and paraffinic white oil at 20–40 phr depending on target Shore A 25–35. Peroxide crosslinking is not used because the styrenic domains provide physical crosslinks with reversible recovery. Recycled content above 15 wt% reduces tear strength below 18 N/mm and is not recommended for validation builds.
Processing for prototype midsoles uses a 120–180 t injection molding machine with a shut-off nozzle. Melt temperature is 185–205 °C; mold temperature is 40–55 °C for foamed parts and 25–35 °C for solid prototypes. Injection speed is profiled at 35–65 mm/s to prevent gas nucleation before cavity fill. Holding pressure is reduced to 10–20 MPa for foamed parts; second-stage pressure above 30 MPa collapses cell structure and produces density gradients. Cycle time is 60–90 s for wall sections up to 8 mm.
Terminal finished types include prototype running shoe midsoles, sandal outsoles with siping, cleat cushioning pods, heel crash pads, and orthotic inserts. Operational boundaries: continuous service above 60 °C under compression can produce compression set above 50%; the material is not intended for continuous steam exposure or direct contact with concentrated oxidizing acids.
A 10 mm diameter bulb compressed to 30% deflection between parallel plates provides the seal force reference for ALM TPE-210-S industrial profile prototypes. Values for a 50 Shore A formulation are typically 6–9 N per 100 mm length after 10 min relaxation at 23 °C. A 40 Shore A formulation reduces seal force to 3–5 N but increases compression set at 70 °C by 6–8 percentage points under ISO 815-1:2019. The design conflict is between closing effort and recovery: low-force profiles reduce door closing effort but show visible set after 500 h at 70 °C.
Industrial sealing validation uses ISO 815-1:2019 compression set, ISO 37:2017 tensile properties, ASTM D395-18 Method B constant-deflection compression set, DIN ISO 34-1:2015 tear strength, ISO 1629:2013 materials nomenclature, and ASTM D471-16a immersion in IRM 903 oil at 100 °C for 70 h. These references permit direct comparison with EPDM and PVC seals in equivalent industrial applications.
Formulation additions for industrial sealing profiles include paraffinic oil at 25–45 phr, calcium carbonate at 5–10 wt% to reduce surface tack and improve die stability, and a hindered phenolic antioxidant at 0.2–0.4 wt%. For coextruded profiles with a rigid polypropylene spine, 2–4 wt% maleic anhydride grafted PP tie layer is added to the skin layer. Carbon black at 1.0–2.5 wt% provides UV resistance for exterior profiles.
Profile extrusion is run on a 45 mm single-screw extruder with L/D 30:1, screen pack 60/80/60 mesh, melt temperature 200–215 °C, and die head pressure 8–12 MPa. Draw ratio is controlled at 1.05:1; higher draw ratios cause surface melt fracture on glossy skin layers. Vacuum sizer water temperature is 20–30 °C. Post-extrusion annealing at 60 °C for 4 h reduces orientation-induced shrinkage to below 1.5%.
Terminal profile prototypes include appliance door gaskets, enclosure edge seals, filter housing gaskets, HVAC damper weather stripping, and transit vehicle window glazing seals. Operational boundary: continuous immersion in mineral oil concentrates may cause volume swell above 25% depending on paraffin content; hot water contact above 90 °C with aqueous chloramine is outside the intended service envelope because surface degradation accelerates under combined oxidative and thermal load.
During impact wrench and rotary tool grip prototyping, adhesion of ALM TPE-210-S to PA6-GF30 and PC/ABS substrates depends on melt contact temperature and substrate surface polarity. If the substrate surface remains below 120 °C, peel adhesion under ISO 8510-2:2008 may fall below 2 N/mm. Preheating the tool housing to 130–150 °C with infrared emitters before overmolding raises peel adhesion to 4–6 N/mm and shifts failure from interfacial delamination to cohesive rubber tearing. This transition is the target for vibration-damped grip validation because it confirms that the TPE skin, rather than the adhesive bond line, is the energy-absorbing layer.
Grip prototype risk assessment references hand-transmitted vibration under ISO 5349-1:2001 and ISO 13753:2008, electrical safety under IEC 62841-1:2014 for hand-held power tools, and chemical compatibility under ASTM D471-16a. The overmolded assembly is tested for damping at octave-band frequencies from 8 Hz to 100 Hz; published data for ALM TPE-210-S at frequencies above 100 Hz is limited, so prototype validation should include dynamic mechanical analysis on the specific tool geometry.
Formulation for grip prototypes uses a 50–55 Shore A grade with 2–4 wt% maleic anhydride grafted styrene-ethylene/butylene-styrene tie concentrate, carbon black at 1.5–3.0 wt% for UV and surface resistivity control, and a slip/antiblocking package at 0.5–1.0 wt% for cutting-fluid resistance. Extender oil is maintained at 15–25 phr rather than high-oil soft grades to limit migration into labels and matte paint.
Insert overmolding uses 80–120 t hydraulic machines with melt temperature 190–210 °C, mold temperature 50–70 °C, and fill time 0.6–1.2 s. The TPE skin wall thickness is 2.0–3.5 mm, gated through a fan gate at the low-stress end; hold pressure is 20–35 MPa for 5–8 s, cooling time 18–25 s. Surface texture VDI 30–33 is selected for tactile slip resistance, and ejector pin marks are recessed 0.2 mm below the grip surface.
Terminal prototypes include pistol grip overmolds for cordless rotary tools, anti-vibration side handles for demolition hammers, battery pack sealing gaskets, trigger switch boots, and inspection equipment grip handles. Operational boundary: exposure to chlorinated cutting fluids or brake fluids above 40 °C may cause surface swelling above 10% and adhesion loss; compatibility testing under ASTM D471-16a with the specific immersion fluid is required.
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In laser-sintering prototyping of flexible components, ALM TPE-210-S Prototyping Polymer is specified where repeated bending, compression, or sealing recovery must be examined before rigid production tooling is committed. The material belongs to the thermoplastic elastomer powder class used in powder-bed fusion, but product-specific lot data are not uniformly published; therefore, incoming material should be controlled through the manufacturer’s certificate of analysis and a standardized test sequence. The designation TPE-210-S separates the product from rigid polyamide-12 and from TPU powder feedstocks by expected lower modulus, higher elongation, and different processing sensitivity. Primary specification values relevant to prototype validation include durometer hardness under ASTM D2240-15e1, tensile stress and strain under ASTM D638-14, tear strength under ASTM D624-00(2020), compression set under ASTM D395-18 Method B, and density under ASTM D792-20. When a prototype is intended for sealing or wear contact, tear and compression set data are more informative than tensile strength alone.
For elastomer powders, the usable volumetric energy density is bounded by a low-energy coalescence threshold and an upper thermal degradation threshold. On powder-bed fusion platforms equipped with 30 W CO₂ lasers and spot diameters of 0.4 mm to 0.7 mm, applied energy density ED is calculated from laser power P, scan speed v, and hatch spacing h as ED = P/(v·h). The numerical value is expressed in J/mm². For elastomer powders in the class of TPE-210-S, a workable ED window commonly falls between 0.015 J/mm² and 0.08 J/mm²; however, the product-specific window for ALM TPE-210-S should be established by a build parameter matrix rather than transferred from PA12. At the lower boundary, incomplete particle coalescence yields anisotropic tensile properties and low elongation at break, particularly in the Z-direction, when tested in accordance with ASTM D638-14 on laser-sintered type IV specimens. At the upper boundary, thermal degradation produces yellowing detected by a b* shift greater than 2 units measured under ISO 11664-4:2016, reduced elongation, and over-sintering that consumes clearances below 1.0 mm.
The powder bed temperature should remain below the melting onset recorded by differential scanning calorimetry under ISO 11357-3:2018. Build chamber setpoints for this material class typically lie between 120 °C and 155 °C; for ALM TPE-210-S, the operating point is selected from the first-heat melting peak and re-crystallization temperature obtained at 10 K/min. If the bed temperature approaches the softening range, particle stickiness raises recoater torque and reduces powder flow. The condition can be detected by an increase in the angle of repose above 35° or a reduction in apparent density measured by ASTM D1895-17 Method A. Sieve analysis should be performed with an upper sieve of 150 µm or finer to remove fused agglomerates. Batch-to-batch melt flow rate should be recorded even though melt-flow data under ISO 1133-1:2022 do not directly predict sintering kinetics, because the powder-bed process lacks continuous screw shear. Used powder should be refreshed with virgin material according to the supplier’s recommended ratio, often in the range of 30% to 50% virgin powder; published data for ALM TPE-210-S at low or high refresh fractions is limited, so density and tensile coupons should be printed at the intended refresh ratio.
On manufacturing SLS systems with build volumes near 381 mm × 330 mm × 457 mm, bed temperature non-uniformity is commonly controlled to within ± 2 °C. The centre of the build envelope typically cools more slowly than the frame, which can increase part density at the centre and reduce dimensional accuracy at the edges. An infrared pyrometer used for closed-loop bed control may read 3 °C to 5 °C lower when recycled powder alters surface emissivity; calibration should be performed with the actual powder lot and a black-body reference. The first production-screening build should therefore spread nine tensile specimens across the build platform to map property uniformity under ASTM D638-14.
Scan strategy also affects seam geometry and residual stress. For TPE-210-S, hatch spacing below 0.10 mm can increase energy density and cause over-sintering, while hatch spacing above 0.25 mm can produce visible fusion lines and lower part density. Layer thickness is commonly fixed at 0.10 mm to 0.12 mm for this powder class. Thicker layers reduce resolution and require higher energy density; thinner layers improve surface finish but increase build time. The optimal layer height is confirmed with a stair-step artefact measured under ISO 4287:1997. Because elastomer powders can shift during recoating, recoater speed below 300 mm/s is generally recommended for parts with fine unsupported walls. Published data for ALM TPE-210-S at recoater speeds above 300 mm/s is limited; process development should include a recoater robustness build with thin-walled and unsupported features.
Laser-sintered elastomer specimens require conditioning before mechanical testing. Specimens are conditioned at 23 °C and 50% RH for 24 h in accordance with ISO 291:2019 or ASTM D618-21. Moisture uptake can plasticize the polymer; therefore, dry-condition testing at 0% RH may be used for components intended for desiccated service. A lot acceptance protocol includes XY and Z type IV tensile bars and a die-C tear specimen. If elongation at break falls below the previous lot by more than 20%, the powder should be dried and retested; if the loss persists, laser power calibration and bed thermography should be checked before accepting the lot. Published data for ALM TPE-210-S lot-to-lot variation is limited, so these limits should be derived from internal process capability data.
Supplier certificates of analysis for TPE-210-S should be translated into a screening protocol that distinguishes useful flexible behaviour from superficial hardness data. The table below lists the minimum measurements used for prototype acceptance, along with the standards and test conditions that can be applied to laser-sintered plaques or tension specimens.
| Measurement | Test method | Typical screening condition | Interpretation for flexible prototypes |
|---|---|---|---|
| Hardness | ASTM D2240-15e1 | 23 °C, 6.0 mm plaque | Lot consistency; insufficient for seal design |
| Tensile stress and elongation | ASTM D638-14 | 50 mm/min, type IV, XY and Z | Detects interlayer coalescence limits |
| Tear strength | ASTM D624-00(2020) Die C | 500 mm/min | Indicates notch sensitivity in bellows and gaskets |
| Compression set | ASTM D395-18 Method B | 22 h at 70 °C | Approximates sealing force retention |
| Density | ASTM D792-20 | 23 °C | Confirms powder fusion and porosity level |
| Powder moisture | ISO 15512:2019 | Karl Fischer titration | Controls agglomeration and surface defects |
ALM TPE-210-S is not a direct drop-in replacement for PA12 in prototype builds. PA12 components exhibit high modulus, semi-crystalline rigidity, and low elongation, whereas flexible TPE prototypes are specified for low modulus and strain recovery. Test selection differs accordingly. For rigid PA12, flexural modulus is reported under ASTM D790-17; for elastomer SLS parts, tensile stress at 100%, 200%, and 300% strain is more informative because the secant modulus changes with extension. Tensile testing of laser-sintered elastomers may follow ASTM D638-14 adapted to type IV geometry, while rubber-like sheet stock may be tested under ASTM D412-16. Tear strength is often more critical than tensile stress in prototypes with notches or sharp corners and is measured by ASTM D624-00(2020) Die C or ISO 34-1:2022 trouser method. A living hinge or sealing lip may fail by tear initiation before the ultimate tensile stress is reached.
Compared with TPU powder grades, TPE-210-S may differ in hard-segment content, Shore hardness range, hydrolytic stability, and moisture uptake. Published data for the specific TPE-210-S formulation is limited; however, at the class level, two TPU formulations with identical Shore hardness can differ in compression set by a factor of two and in tear strength by more than 50%. Hardness under ASTM D2240-15e1 should therefore not be the sole selection criterion. When the product is evaluated as a replacement for a TPU powder in a gasket-like prototype, compression set after 22 h at 70 °C under ASTM D395-18 Method B and low-temperature flexibility under ISO 2921 or ASTM D1053-16 should be assessed. Hot water or humid air exposure requires tensile retention after immersion per ISO 1817:2022 or ASTM D471-16a; compatibility testing on printed coupons is required because product-specific immersion data for ALM TPE-210-S are not available.
When the prototype is intended to represent an injection-molded TPV production component, process comparison can be performed on a 100 tonne injection molding machine with a 20:1 L/D general-purpose screw and barrel temperatures from 180 °C to 220 °C. The SLS prototype lacks the shear history and knit lines present in the molded component. Insert force and snap-fit retention should be compared using a force gauge calibrated to 0.5 N or better, not simply inferred from Shore hardness.
In storage and handling, TPE-210-S powder is subject to moisture uptake and particle agglomeration above a critical relative humidity. The material should be kept in sealed containers below 30% RH and below 30 °C. If exposed to ambient air at 60% RH or higher for more than 8 h, vacuum drying at 50 °C to 70 °C for 4 h to 8 h is typically required before processing. Powder moisture is monitored by Karl Fischer titration in accordance with ISO 15512:2019 or equivalent. Spent powder from the build and overflow chambers should be sieved through a mesh equal to the powder’s nominal upper particle size, typically 150 µm or finer, to remove fused agglomerates and debris. Mixing used powder with virgin stock should follow the supplier’s refresh ratio; without verified lot-specific data for ALM TPE-210-S, the safe ratio is established by printing tensile bars at 0%, 30%, 50%, and 70% used powder fractions and comparing elongation at break and density under ASTM D638-14 and ASTM D792-20. Cross-contamination with PA12 powder must be avoided because residual rigid particles become hard inclusions that initiate tearing under ASTM D624-00(2020).
Elastomer SLS prototypes do not respond to abrasive finishing in the same way as rigid PA parts. Glass-bead blasting at 4 bar to 6 bar with 100 µm to 180 µm media removes semi-sintered powder from the surface but can also induce local compression and heating. If ALM TPE-210-S is blasted at 5 bar with a standoff distance below 50 mm, the surface may show smearing, gloss change, or embedded media. Dimensional measurements after blasting should be delayed for at least 2 h to allow elastic recovery, and wall thickness should be compared with the CAD model in multiple part orientations. When a sealing lip or living hinge requires a smooth surface, a two-stage post-treatment of soft bead blasting followed by vibratory tumbling with non-abrasive ceramic media is sometimes used. The effect of tumbling on compression set and edge tear should be evaluated under ASTM D395-18 Method B and ASTM D624-00(2020) Die C, because microcracks may not be visible until cyclic loading is applied. Published data for ALM TPE-210-S after these specific finishing operations is limited; process qualification should include surface inspection at 50× and 200× magnification and tensile testing of at least 5 specimens per build orientation.
Regulatory status for ALM TPE-210-S should be confirmed from the supplier’s REACH and RoHS declarations. EU RoHS Directive 2011/65/EU restricts lead, mercury, cadmium, hexavalent chromium, PBB, and PBDE; a lot-specific raw-material compliance statement is required before claiming conformance. For skin-contact or medical prototypes, the absence of an ISO 10993-5:2009 cytotoxicity report or USP Class VI statement means that biological safety has not been established. Food-contact use under FDA 21 CFR 177.1680 or EU Regulation 10/2011 requires supplier migration data and cannot be inferred from the polymer name alone.
Seal prototypes are tested for leak rate using ASTM F37-06(2013) at internal pressures from 0.1 MPa to 0.3 MPa. Because SLS surfaces are not as smooth as molded surfaces, flange sealing tests should include controlled bolt torque and a conformable gasket face. Bellows prototypes are flexed on a servo-pneumatic linear actuator with displacement amplitudes between 2 mm and 5 mm at 1 Hz. Surface crack initiation is inspected at 20× magnification after 1,000, 5,000, and 10,000 cycles. These tests provide short-term dynamic screening and do not replace long-term production validation.
